Missing vendor prefixes with styled-jsx

[stringparser]

Have to add https://github.com/giuseppeg/styled-jsx-plugin-postcss plugin and postcss for this.

[stringparser]

Have to review. Would be very sweet to either get rid of styled-components and use this (because the source maps are way nicer) or find out if it is possible to use postcss (looks is still a bit early).